package thread;
/**
 * 常见的并发安全API: StringBuilder和StringBuffer
 * 1.StringBuilder不是并发安全的(异步)，多线程场景下不能用
 * 2.StringBuffer是并发安全的(同步)，多线程场景时使用
 */
public class SyncDemo3 {
    public static void main(String[] args) {
        StringBuilder sb = new StringBuilder();
        //StringBuffer sb = new StringBuffer();
        Thread t1 = new Thread(){
            public void run(){
                for(int i=0;i<1000;i++){
                    sb.append("abc");
                }
            }
        };
        Thread t2 = new Thread(){
            public void run(){
                for(int i=0;i<1000;i++){
                    sb.append("def");
                }
            }
        };
        t1.start();
        t2.start();
        try {
            Thread.sleep(50);
        } catch (InterruptedException e) {
        }
        System.out.println(sb.length()); //6000?
        System.out.println(sb);
    }
}
















